Bigint.BigInt.gcd: def of bend-kit-bignum@0.1.0.0
Import: import bend-kit-bignum@0.1.0.0/bigint.bend as Bigint
Lines 460-465 of bend-kit-bignum@0.1.0.0/bigint.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-bignum@0.1.0.0/bigint.bend&start_line=460&end_line=465

import Base

# Never negative; gcd(0, 0) is 0.
def BigInt.gcd(a: BigInt, b: BigInt) -> BigInt:
  match a b:
    case BigInt{sa, +x} BigInt{sb, +y}:
      BigInt{False{}, Mag.gcd(
        Nat.add(Nat.mul(Nat.add(Mag.len(x), Mag.len(y)), 20n), 2n), x, y)}

Uses (6):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.mul
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bignum@0.1.0.0/bigint.bend&name=BigInt
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bignum@0.1.0.0/bigint.bend&name=Mag.gcd
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bignum@0.1.0.0/bigint.bend&name=Mag.len